Automatic ringing system.



A. H. WEISS. AUTOMATIC RINGING SYSTEM. APPLICATION FILED AUG. 17, 1910.RENEWED NOV. 10, 1911.

1,029,649,, Patented June 18,1912.

fmrenfur V g: E7 HLfrEd H-UUEIEE .NIE stares nub,

ALFRED I-I. WEISS, OF WILME'I'TE, ILLINOIS, ASSIGNOR T0 KELLOGGSWITGHBOABD 7 AND SUPPLY COMPANY, OF CHICAGO, ILLINOIS, A CORPORATIONILLINUIS. V

AUTGMA'IIC RING-1N6 SYSTEM.-

Patcntedlltune is, rate.

Application filed August 17, 1910, Serial No. 577,657. Renewed November10, 1911. Serial No. 659,640.

To all whomlit may concern:

Be it known that I, ALFRED II. Wares, a citizen of the United States,residing in VVilmette, county of Cook, and State of Illinois,

have invented certain new and useful Improvementsdn Automatic RingingSystems, of which the following is a specification.

My invention relates to common battery telephone exchange systems, andmore particularly to a system of automatic ringing for such systems, bymeans of which the desired subscribers bell is rung automatically by theact of inserting the plug in the ack of the line, the ringing of thesubscribers bell continuing until the subscriber responds to the call byremoving his telephone receiver from the switch-hook, when the ring ingis automatically discontinued. I prefer Both of the telephone lines Aand B have' the same equipment and the same reference numerals are usedto indicate like parts in both lines.

The substation apparatus shown consists of bell 1 and condenser 2connected in series when the telephone receiver is upon its hook, forsignaling purposes, the bell being removed from thecircuit when thereceiver is removed from the hook for conversation, and a path forcurrent is then closed through the transmitter 3 and the impedance coil4, the voice currents being shunted through the receiver 5 and thecondenser 2. Any form of substation circuit may be employed in lieu ofthat described. Thelimbs of the' telephone iines terminate in jackcontacts 6, the sleeve contacts of the jacks being connected to theground 7 through the winding of the cut-oftrelay 8. A line relay 9 andline lamp 10 are also provided for each line. Two supervisory relays 11and 12 are preferably provided for the answering end of the cordcircuit, these relays jointly controlling the circuit of the supervisorylamp 1'3. Corresponding supervisory relays lit and 15 are provided forthe calling end of the cord circuit, said relays being adapted tojointly control the circuit of the supervisory lamp 16. The usualoperators listening key 17 and head telephone 18 are provided, and atesting coil 19 is associated with the listening key in such a manner asto inform the operator of the idle or busy condition of the, desiredline when the line is tested by producing the usual click in hertelephone receiver.

Referring more particularly to the automatic ringing features of thesystem, I provide suitable generators 20, 21, 22 and 28 and impedancecoils 24, 25, 26 and 27, a control relay 28, a slow-acting relay 29, anda non inductive resistance-30 with key mechanism and circuits forsuitably. associating these elements with those previously mentioned.For the purpose of explaining the operation of the system, we willassume the subscriber on the line A desires a connection with one of thesubscribers on the line B. He will remove his receiver from the hook,closing a path for currentfromithe battery 31,.

through conductor 32, line relay 9, the limbs of the telephone line,including the substation apparatus to ground 33. The linerelay willrespond to this current attracting its contact spring and lighting theline lamp 10. The operator attracted by this signal will insert heranswering plug 34 in the jack 6 of the calling line which will close apath for current from the battery 35, through the sleeve supervisoryrelay l2, sleeve contacts of the plug and jack. conductor 36 and thewinding of the cut-off relay 8 to the ground 7. The cut-off relay willattract its contact springs opening the circuit of the line relay 9 atone contact to retire the line signal 10, and removing the ground 33 atthe other contact connecting that limb of the line with the sleeve ofthe jack. A portion of the cur rent flowing to ground through the cutotirelay 8 will flow over the-limbs of the telephone line and through thesubstation apparatus, returning to the battery 35 through the tipcontacts of the jack and plug and thwinding of the supervisory relay 11.The supervisory relay 12 is energizedas long-as; the plug is in the jackthrough the local circuit provided bythe' denergization of relay 11 whenthe subscriber replaces his receiver upon the hook at the conclusion ofthe conversation.

The. operator after inserting the plug 34 in the jack of'the callingline, throws her listening key 17 and inquires the number of the desiredsubscriber. Ascertaining that a subscriber upon the line B is desired,she tests the condition of the line by touching the tip of hercallingplug 37 to the sleeve contact of the line. If there is a connection pfor each station upon the line, the arrangealready established with theline at some other position of the switchboard, a potential above thatof earth will exlst upon the sleeve contact of the multiple jack of theline, and whenthe tip of the plug is touched to and removed from thesleeve contact, battery will flow through the tip strand 38 of the cordcircuit, the normally closed back contact of supervisory relay 15,conductor 39, contact 40 on the listening key to ground through theimpedance coil 19. The discharge from the impedance coil 19 during thetesting process will pass through the tertiary winding 41 to groundthrough battery 31, thus notifying the operator by an inductive click inher telephone receiver, that the lineis busy. If no connection existswith the desired line, no current will flow through the path just tracedwhen the line is tested, and 110 click will be received in the operatorsreceiver.

If the line is idle,'the operator .will insert the plug 37 in the jackof the desired line, closing a path for current from battery 31, overconductor 42, the winding of supervisory relay 15, sleevestrand 43, andsleeve contacts of the plug and jack to ground through the windingofcut-ott relay 8. The cut-otf relay will'attract its contact springs,opening the circuit of the line relay 9 at one contact, preventing theoperation of the line lamp 10- and removing the ground 33'from the otherlimb of the line, connecting said last mentioned limb with the sleevecontact of the jack. 'Current in this path will operate the supervisoryrelay 15 which will attract contact spring 44, removing the testingconductor 39 from the tip of the plug and establishing the continuity ofthe tip cord strand ,38'at the front contact of said relay forconversation. Contact spring 45 of supervisory relay 15 will also beattracted, closing the circuit of supervisory lamp. 16 at this point,but due to the fact that the subscriber has not yet removed histelephone from the hook, tip supervisory relay 14 is not yet energized,thus lighting the supervisory lamp lfifrom battery 31, over conductors46, 47, 48 and 49 to ground at the closed contacts of supervisory relay14. When the called subscriber re sponds, supervisory relay 14 will beenergized over the telephone line, opening the circuit of thesupervisory lamp 16 at that point, thus indicating to the operator thatthe subscribers" are in conversation. Also, when the called subscriberreplaces his telephone upon the hook at the termination of theconversation, a path for current through the supervisory relay 14 willbe interrupted, permitting its spring to drop back, reestablishing thecircuit of the supervisory lamp 16 to indicate to the operator that theconversation is terminated.

I preferably provide a separate generator ment being such that the bellat each station is responsive to current from one generator only. Iprefer to accomplish this selective signaling by providing differentfrequencies of ringing current for each generator and tuning the bellsat the substations to respond to the different frequencies of current.It should be understood, however, that this'method of selectivesignaling is shown for the purpose of describing the operation of myautomatic ringing system, and

that other methods of selective or non-selective signaling may beemployed with my automatic ringing arrangement.

I have shown four generators 20; 21, 22 and 23 preferably adapted todeliver alternating currentito the line of four-thousand,three-thousand, two-thousand and one-thousand cycles respectively perminute, the bells of the four subscribers stations upon the line B beingadapted to respond to. these frequencies. Impedance coils24, 25,26 and27 are adapted to be connected between ground and the alternate contactof each generator key. An additional key contact 50 is also provided,which is adapted to be closed momentarily when any of the generator keysare closed, the arrangement being such that the generator will remainclosed to continue the operation of ringing, while the key 50 Will beclosed momentarily and then released to restore to its normally opencondition.

The operator having now ascertained the number of the subscriber desiredand inserted the calling plug 37 in the jack of the line B, will operatethe ringing key corresponding to that station. We will assume that sheoperates ringing key 51. Ringing key 50 will also be closed momentarilywhich will close a path for batt ery current through the control relay28 which may be traced from battery 31, over conductors 46 and 47, thewinding of said control relay'QS, conductor 52, key contacts 50- andconncaaeae ductors 53, 54:, 55 and 4:9 to ground at the contact ofsupervisory relay 14; Control relay 28 will be energized by this flow ofcurrent and attract its contact springs, closing a locking circuit foritself which may be traced from battery 31, over conductors 46 and lr',the winding of said relay, con tact 66 conductors'fifi, 54c, 55 and 49to ground at the'contacts of supervisory relay 1a. The energizationofcontrol relay 28 opens the tip and sleeve strands of the cord circuit atback contacts 57 and 58 to prevent the ringing current from passing backover the line of the calling subscriber.

also closes the path for ringing current at its front contacts 59 and60, the path for said ringing current being traced from generator 20,through the interrupter 61, ringing key contact 51, condenser 62,contact 59 of control relay '28, tip strand 38 of the cord circuit, thelimbs of the telephone line and the substation apparatus, sleeve strand43 of te cord circuit, contact 60 of control relay 28, the non-inductiveresistance to ground through battery 31. Ringing current in this pathwill be applied intermittently due to the rotation of thecircuit-breaker 61 until the called subscriber til fits armature 65,

responds by removmg his telephone receiver from the hook. It W-lll benoted that the return path for the'ringing current includes the windingof supervisory relay 15 and conductors 4C2 and l6 to battery 31, and thenon-inductive resistance 30 is placed in a shunt about the supervi oryrelay 15 to prevent the ringing current from chattering vsaid relay.

It will be noted that a path for current also exists from the contact63, through relay 29, conductor 64, the depressed ringing key contactand the associated impedance coil 24, to ground. This path is providedfor battery current when the subscriber responds to the call, saidbattbry current being adapted to energize relay 29 and attract thusopening the locking circuit of control relay 28 and ringing apparatus tonormal condition. Assuming'now that the subscriber removes his receiverfrom the hook in response to the signaling current from generator 20,through traced from battery 31, over conductors 46 and 42, the windingof supervisory relay 15, sleeve strand 43, sleeve contacts of the plugand jack, the limbs of the telephone line, the tip contacts of the jackand plug, tip strand 38 of the cord circuit, front contact 63 of controlrelay 28, the winding of relay 29, conductor 6% and the ringing key cont acts to ground through impedance coil 24'.

Current in this path will energize relay 29,

attract its" contact spring 65,

which will locking circuit of control relay opening the W hen thefrequency of restoring the 28 and permitting its contact springs to dropback. The continuity of the cord corcuit will be reestablishedat backcontacts 57 and 58 of the control relay, the ringing current will be cutoil at intermediate-con tacts 59 and 60 of said relay and the circuitsof the relays 28 and 29 will be opened at front contacts 63 and 66, thusrestoring the ringing apparatus to normal condition. contact 68 is open,the battery current flowing to ground through relay 29 will be divertedthrough contact '57, and conductors 67 and 68 to ground through tipsupervisory relay 14. Said relay will be energized opening the circuitof thesupervisory lamp 16 which will be extinguished to. notify theoperator that the called" sub- I scriber has responded.

The impedance coils 24, 25, 26 and 27 are of very high impedance to thealternating to permit the passage of very little of the ringing current,and relay 29 is preferably per shell to prevent its possibleenergization in response to such alternating ringing current as may passthrough the impedance coils 24F, 25, 26 or 27. It is not responsivetherefore to the ringing current, which is practically all forced by theimpedance coils to take the alternate path over the telephone line andthrough the substation ringer. The impedance coils, however, allord aready path for the battery current when the subscriber responds to thecall, and relay 29 is energized bythe flow of batterycurrent as abovedescribed. The battery 31 is preferably ofhigh voltage, from fort-y tofortyeight volts, in order to insure the operation of relay 29 over aline of high resistance.

The low frequency ringing current adaptator 23 will not pass readilythrough the condenser 62 and the condenser at the' subs scribersstat-ion in series, and for this low' current, the non-inductiveresistance 69 is provided for the ringing curprovided with a cop- I rentinstead of the condenser 62 which is used for the three higherfrequencies. The generator circuit is common to a plurality of cordcircuits at the point 7 0 and the im pedance coil is common to aplurality of cord circuits at the point 71. In ringing two or moresubscribers at one time from the low frequency generator 23, the relay29 of each -cordcircuit being rung would be. bridged across the commonpoints ,70 .and 71. Now if the n0n-inductive resistance 69 were lowenough, there might be a tendency to operate the said several relays 29when any one of the subscribers being called by the low frequencycurrent, would respond.- This would be caused by current from bat tery31 flowing out over the lined the responding subscriber, to contact 59andthen t a 7 0. From there it would To prevent this possible prematurerelease of any of the ringing apparatus, the noninductive resistance 69ohmic resistance, preferably one thousand ohms. It would be necessaryfor the battery current to flow through two of these coils in series toaccomplish the premature release of the ringing apparatus and onethousand ohms has been found sufiicient to prevent such an occurrence. 7

If it is desired to use a battery of low voltage such as twenty ortwenty-four volts for talking and slgnaling purposes, a booster orassisting of releasing relay 29 upon the response ofa called subscriber,may be employed. I have shown battery purpose, sixty volts beingsuificient for the purpose when used in connection with a twenty-fourvoltbattery for talking purposes. The battery 72 would be connected atthe point 73 and the conductor between this point and. point 74: wouldbe removed. With the circuit so arranged, when the operator closes the.ringing springs and relay 28 is energized, there will result a re versalof current flow in the relay 15, due to the closing of contact 60 ofsaid relay 28. This reversal is due to the voltage-of battery 72overcoming that of the battery 31. The reversal of current throughsupervisory relay 15, would therefore momentarily deenergizc said relayand there would be a tendency to open the contact 45, thereby openingthe locking circuit of rel ay.28. To prevent said relay 28 fromretracting its armature and moving its contacts to normal when a highvoltage or booster battery is employed, the said relay 28 is providedwith a copper shell upon its core, rendering sluggish in its action.Therefore, should the relay 15 momentarily retract its armature therelay 28 will retain its armature in an attracted position,preventingits springs from restoring to normal, I

Upon the response of the called subscriber current will flow frombattery 72 to resistance 30, contact 60 to sleeve strand 43, the sleevecontact of the plug and jacket, and then over the path previouslydescribed in connectionwith the battery flow from battery 31 uponresponse of the called subscriber.

I claim: I

'1. In a telephone system, the combination with a calling and a calledsubscribers telephone line, an operators link circuit connecting s'aidlines, a source of ringing current, a disconnect relay, a ringing key, acon- 18 made of high battery for the purpose 72 in dotted lines for thisand ringing current in separate bridges of said called line throughcontacts .of said control relay and disunite the calling and calledlines, and means under the control of the called subscriber to energizesaid discon'nect relay, moved and the is established.

2. In a telephone system, the combination with a calling and a calledsubscribers telephone line, acord circuit connecting said lines, asource of ringing current, a disconnect relay, means for connecting saidourrentand said relay in separate permanent bridges of said called lineuntil aresponse of the called subscriber is secured, a. source ofbattery current, and means actuated upon response of the calledsubscriber to include said {battery current in said relay bridge wherebysaid relay is energized, and means whereby said bridges are re-.

continuity of said connection effective uponthe energization of saidrelay subscribers telephone line, a link clrcuit for connection thereto,a source of ringing current, a source of battery current, means forsimultaneously connectlng said currents in separate bridges of saidcalled line, a relay included in said battery bridge, a signal for saidsubscribers line actuated responsive to said ringing current bridge,andmeans controlled by the called subscriber to render the batterybridgeefi'ective to energize said relay, whereby said ringing currentbridge is disconnected.

4. In a telephone system, the combination with a called subscriberstelephone line, of a cord circuit connected thereto, a super-, visorysignal actuated responsive to said connection, a. ringing key actuatedto signal the called subscriber, a control relay energized responsive tosaid actuation to disunite 1 the answering and calling ends of said cordcircuit While the called line is being signaled, a battery, asupervisory relay disconnected from the means actuated upon the responseof the called subscriber to denergize said control relay to establishthe continuity of said cord circuit, said su ervisory relay beingthereupon connected said line, said signal being -e aced upon'theenergization of said supervisory relay.

5. In a telephone. system, the combination with a cord circuit, acalling and a called subscribers telephone line connected thereby, agrounded source of ringing current and a grounded source of batterycurrenthavi'ng v to the calling 'end of said cord circuit .and energizedby battery over.

calling end of said cord circuit,

iis

their ungrounded terminals connected to opposite limbs of the calledline, said ringin current serving to signal the called subscriber, adisconnect relay having one ter-.

minal connected to the limb which is con-' nected to the ringlng currentand the other terminal to ground, means for simultanethrough said relay,and -a switch at the called substation for rendering the last said meansinefiective, whereby said relay is energized by said battery over saidline to disconnect said ringing current.

i 6. In a telephone system, the combination with a called subscriberstelephone, a pair of conductors therefor leading to the exchange, asource of signaling current in bridge of said conductors for signalingthe called subscriber, a battery, and a relay connected in a separatebridge of said line, an impedance coil included in the latter bridge toprevent shunting said signaling current by said bridge, means at thesubstation for preventing a flow of battery current through said relayover the limbs of said line, and a switch at the substation actuatedupon response of the called subscriber to render the latter meansinefiective whereby said relay is energized to disconnect said signalingcurrent,

7. A telephone system comprising a called substation telephone line, alink circuit connected thereto, a source of ringing current, a batteryand a relay, means for connecting and simultaneously maintaining saidringing current, and said battery and relay in and State of Illinois,

separate bridgesof the cord-circuit and line, a signal at the calledsubstation responsive to said ringing current, means at the substationfor preventing a flow of current from said battery through said rela atthe substation actuated to effect a flow of current from said batterythrough said relay whereby said relay is energized and said current isdisconnected.

8. A telephone system comprising acalled substation telephone line, alink circuit connected thereto, a grounded source of ringing currentconnected to the tip conductor of said link circuit, a relay andimpedance coil serially connected from ground to said tip conductor, agrounded source of battery current having its ungrounded terminalconnected to the sleeve conductor of saidlink circuit, a signal at thecalled substation responsive to said ringing current, means at thesubstation-to prevent a flow of current from said battery through saidrelay and impedance coil, and a switch at the -substation actuated toefiect a'flow of current from said battery through said relay andimpedance coil, whereby said relay is energized to cause disconnectionof said ringing current from said tip conductor.

Signed by me at Chicago, county of Cook in the presence of twowitnesses.

ALFRED H. WEISS. Witnesses:

MARJORIE EJGRIER,

WM. BEBGHAHN.

and a switch

